references/d3-module-map.md

# D3 Module Map

## What Problem This Solves

This reference shows which D3 modules solve which problems so the skill does not treat D3 as one undifferentiated blob.

## When to Use It

Use this when choosing D3 building blocks for a chart.

## Key Takeaways

- `d3-array`, `d3-scale`, `d3-axis`, and `d3-shape` cover a large portion of custom chart work.
- `d3-zoom`, `d3-brush`, and `d3-drag` are the interaction backbone.
- `d3-force`, `d3-hierarchy`, and `d3-geo` are specialized tools that should be used only when the data structure demands them.

## Common Mistakes

- Pulling in force layout or hierarchy helpers just because they exist.
- Treating selection code as the only thing D3 provides.

## Adjacent Skills

- `../SKILL.md`
- `../../geospatial-and-cartographic-visualization/SKILL.md`

## Source Links

- [D3 API](https://d3js.org/api)